Some of you may noticed that I'm no longer reviewing as many different external batteries. Unfortunately, there has been very little innovation in this sector of smartphone accessories. One of the new trends I have seen so far is the increase in external battery capacity to keep up with new power hungry big screen phones and tablets. As you increase the capacity you also increase the charging time for the battery itself where in some cases even overnight charging is not enough to get to 100% ready. Realizing this shortfall, UNU engineers decided to come up with a new line of Ultra-X fast charging batteries which I got a chance to review. Here is what I found.

Since both of these batteries have a very similar design and functionality with the only difference of capacity and a number of charging ports, I decided to combine review of GO (3,000 mAh) and TOUR (10,000 mAh) Ultrapack batteries together. Both arrived in a very similar packages, only scaled in size, with a clear message of 8x Faster charging rate. The package also has a lot of useful info about the benefits of using this battery, in terms of additional hours in extended functionality, but it's all relative to your use and I typically recommend taking it with a grain of salt. The most important thing you have to realize is that once you are away from a power source and need to recharge your phone battery - you now have a portable source on the go. Also, a total advertised capacity of the external battery is not what you are actually going to see because it's based on their internal 3.7V-3.8V voltage which needs to be converted through 5V usb interface where you will loose some of this capacity due to a typical 85%-90% conversion efficiency. Therefore, you need to choose the capacity of your external backup battery based on how long you are going to be away from the power source and how many times you will need to recharge your phone or tablet battery.

With this explanation out of the way, let's take a closer look at the design and special features of UNU Ultrapack batteries. The design of GO and TOUR is almost identical with a piano finish top/bottom surface and softer material sides for a better grip. Both of the batteries have a power button which turns on a hidden LCD screen with a charging capacity info and also turns on a built-in led flashlight (convenient when you are in the dark, like during a power outage). GO features a single USB charging port rated up to 2.1A and TOUR feature a double USB port rated at 1A and 2.1A for a combined output of 3.1A. Another port they share in common is DC input charging port. Unlike most of the other external batteries with micro-usb charging port and a typical 5V/1A charging speed, here you have 12V/2.5A charging port which enables a much faster charging speed of the battery. Just keep in mind, we are not talking about faster charging speed of your phone/tablet battery, but the actual external battery itself.

Faster charging speed, up to 8x faster, means you don't have to wait hours to charge up this battery before you can start using it. As a matter of fact, it has a rapid charging mode where in 15min you get 2,000 mAh of capacity from empty. This means if you are in the rush you can still get a charging capacity boost for this backup battery in only 15min. The only catch is that you have to use a bulky wall AC adapter. It's the only drawback which is a price to pay for a fast re-charging. Another fantastic feature is the built-in LCD screen which tells you exactly in % how much battery left and also tells you how long before battery is full when you charging it up. When not turned on, the display is fully hidden under the top surface. Also, charging mechanism has it's own current regulator to optimize charging speed of your smartphone/tablet. With a smaller capacity GO, I was only able to charge my Note 2 at 1.2A speed. With dual output TOUR, Note 2 was charging at a maximum speed while S5 connected to another port only had 1.3A of charging current not to exceed a combined 3.1A output. It didn't even matter which port I had my phones connected to, either 2.1A or 1A ports were able to charge at max speed individually and current draw was regulated when two phones were connected simultaneously.

Overall, I was very impressed with performance of both batteries and all the additional bonus features they had to offer. Fast charging speed and a detailed LCD screen functionality was a very useful new feature if you are willing to pay premium price for these batteries. I know there are a lot cheaper alternatives with a similar or higher capacity, but you really have to factor in all the additional design features Ultrapack brings to the table in order to have a true comparison. And even so I typically don't review smaller capacity batteries, if you want this Ultra-X fast charging technology and LCD info screen but don't want to drag around a large and heavier TOUR, GO is a perfect solution for that.

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